What are the main anti-angina medications?

Main Anti-Angina Medications

The main anti-angina medications include beta-blockers, calcium channel blockers, nitrates, and newer agents such as ranolazine, ivabradine, nicorandil, and trimetazidine, which should be selected based on patient characteristics, comorbidities, and underlying pathophysiology of angina. 1

First-Line Anti-Angina Medications

Beta-Blockers

• Reduce myocardial oxygen demand by decreasing heart rate, contractility, and blood pressure 2
• Examples include metoprolol, atenolol, and bisoprolol 1
• Target dose should aim for resting heart rate of 55-60 beats per minute 1
• Particularly beneficial in patients with prior myocardial infarction or heart failure 1
• Contraindicated in vasospastic angina as they can precipitate coronary spasm 1
• Use with caution in patients with peripheral artery disease, COPD, or atrioventricular conduction disorders 1

Calcium Channel Blockers (CCBs)

• Two main types: dihydropyridines (amlodipine, nifedipine) and non-dihydropyridines (verapamil, diltiazem) 1
• Reduce myocardial demand by decreasing afterload and enhance oxygen supply through coronary vasodilation 2
• Particularly effective for vasospastic angina, preventing spasm in about 90% of patients 1
• Non-dihydropyridine CCBs should be avoided in patients with heart failure with reduced ejection fraction 1
• Should not be combined with ivabradine due to risk of excessive bradycardia 1

Nitrates

• Short-acting nitrates (sublingual nitroglycerin) provide immediate relief of angina attacks 1
• Long-acting nitrates (isosorbide mononitrate, isosorbide dinitrate) reduce frequency and severity of anginal attacks 1
• Work through venodilatation, reduced cardiac filling pressures, and coronary vasodilation 1
• Require a daily "nitrate-free" interval (10-12 hours) to prevent tolerance 1
• Contraindicated with phosphodiesterase inhibitors and in hypertrophic cardiomyopathy 1

Second-Line Anti-Angina Medications

Ranolazine

• Reduces angina frequency and nitroglycerin use when added to standard therapy 3
• Particularly useful in patients with low heart rate and/or blood pressure 1
• Can be used as add-on therapy when symptoms are inadequately controlled with first-line agents 1

Ivabradine

• Selective sinus node inhibitor that reduces heart rate 1
• Alternative for patients with beta-blocker intolerance 1
• Should not be combined with non-dihydropyridine CCBs 1

Nicorandil

• Potassium channel activator with nitrate-like effects 1
• Useful for vasospastic angina and as add-on therapy 1
• Can be considered when first-line treatments are contraindicated or poorly tolerated 1

Trimetazidine

• Metabolic agent that improves cardiac metabolism 1
• Particularly beneficial in patients with microvascular angina 1
• Can be used as add-on therapy when symptoms are inadequately controlled 1

Treatment Strategy and Combinations

• Start with short-acting nitrates for immediate symptom relief 1
• Initial treatment with beta-blockers and/or CCBs is recommended for most patients 1
• If monotherapy is insufficient, consider combination of beta-blocker with a dihydropyridine CCB 1
• For patients not responding to two drugs, add long-acting nitrates, ranolazine, nicorandil, or trimetazidine 1
• Selection should be tailored to specific patient characteristics:
  • For vasospastic angina: CCBs and long-acting nitrates 1
  • For microvascular angina: ranolazine or trimetazidine 1
  • For patients with peripheral artery disease: avoid beta-blockers or use with caution 1
  • For patients with AV conduction defects: avoid beta-blockers and non-dihydropyridine CCBs 1

Important Considerations

• Meta-analyses show similar efficacy among different anti-anginal drugs for symptom reduction 4
• No anti-anginal medication has been proven to improve long-term cardiovascular outcomes, except beta-blockers when given within 1 year after acute MI 1
• Combination therapy is often required for adequate symptom control 1
• Tolerance to long-acting nitrates can develop with continuous therapy, necessitating a nitrate-free interval 5
• Adherence to medication is crucial for successful angina management 1